Port rdp extension code about freerdp

[awakecoding]

@Beloni: I have just ported the extension plugin interface to FreeRDP 1.0, but I haven't tested it. Since you're one of the few using that interface, could you please test it and report if it works so that we can close this ticket?

[awakecoding]

@Beloni: ping, O.S.Systems is the only one using the extension code that I know of, so we'd need you to confirm that it works! Let me know when you'll have the time

[eduardobeloni]

@awakecoding I problably won't be able to test it this year

[awakecoding]

@Beloni: ok then, how about we close this ticket which was to port the code, and you open a new one if it turns out to not work properly when you end up testing it?

[eduardobeloni]

Agreed